package com.hxgz.steel.util;

import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang.StringUtils;
import org.codehaus.jackson.map.DeserializationConfig;
import org.codehaus.jackson.map.ObjectMapper;
import org.codehaus.jackson.map.SerializationConfig;
import org.codehaus.jackson.map.annotate.JsonSerialize.Inclusion;
import org.codehaus.jackson.type.JavaType;
import org.codehaus.jackson.type.TypeReference;

import java.text.SimpleDateFormat;


@Slf4j
public class JsonUtil {

  private static ObjectMapper objectMapper = new ObjectMapper();

  static {
    //对象的所有字段全部列入
    objectMapper.setSerializationInclusion(Inclusion.ALWAYS);

    //取消默认转换timestamps形式
    objectMapper.configure(SerializationConfig.Feature.WRITE_DATES_AS_TIMESTAMPS, false);

    //忽略空Bean转json的错误
    objectMapper.configure(SerializationConfig.Feature.FAIL_ON_EMPTY_BEANS, false);

    //所有的日期格式都统一为以下的样式，即yyyy-MM-dd HH:mm:ss
    objectMapper.setDateFormat(new SimpleDateFormat(DateTimeUtil.STANDARD_FORMAT));

    //忽略 在json字符串中存在，但是在java对象中不存在对应属性的情况。防止错误
    objectMapper.configure(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES, false);
  }


  public static <T> String obj2String(T obj) {
    if (obj == null) {
      return null;
    }
    try {
      return obj instanceof String ? (String) obj : objectMapper.writeValueAsString(obj);
    } catch (Exception e) {
      log.warn("Parse Object to String error", e);
      return null;
    }
  }

  public static <T> String obj2StringPretty(T obj) {
    if (obj == null) {
      return null;
    }
    try {
      return obj instanceof String ? (String) obj
          : objectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(obj);
    } catch (Exception e) {
      log.warn("Parse Object to String error", e);
      return null;
    }
  }


  public static <T> T string2Obj(String str, Class<T> clazz) {
    if (StringUtils.isEmpty(str) || clazz == null) {
      return null;
    }

    try {
      return clazz.equals(String.class) ? (T) str : objectMapper.readValue(str, clazz);
    } catch (Exception e) {
      log.warn("Parse String to Object error", e);
      return null;
    }
  }


  public static <T> T string2Obj(String str, TypeReference<T> typeReference) {
    if (StringUtils.isEmpty(str) || typeReference == null) {
      return null;
    }
    try {
      return (T) (typeReference.getType().equals(String.class) ? str
          : objectMapper.readValue(str, typeReference));
    } catch (Exception e) {
      log.warn("Parse String to Object error", e);
      return null;
    }
  }


  public static <T> T string2Obj(String str, Class<?> collectionClass, Class<?>... elementClasses) {
    JavaType javaType = objectMapper.getTypeFactory()
        .constructParametricType(collectionClass, elementClasses);
    try {
      return objectMapper.readValue(str, javaType);
    } catch (Exception e) {
      log.warn("Parse String to Object error", e);
      return null;
    }
  }


}
